There shall no strange god be among you; neither shall you worship any foreign god.
Read Chapter 81
Augustine of Hippo
AD 430
13. "Israel, if thou shalt have heard Me, there shall not be in thee any new god" (ver. 9). A "new god" is one made for the time: but our God is not new, but from eternity to eternity. And our Christ is new, perchance, as Man, but eternal God. For what before the beginning? And truly, "In the beginning was the Word, and the Word was with God, and the Word was God." And our Christ Himself is the Word made flesh, that He might dwell in us. Far be it, then, that there should be in any one a new god. A new god is either a stone or a phantom. He is not, saith one, a stone; I have a silver and a gold one. Justly did he choose to name the very costly things, who said, "The idols of the nations are silver and gold." Great are they, because they are of gold and silver; costly they are, shining they are; but yet, "Eyes they have, and see not" New are these gods. What newer than a god out of a workshop? Yea, though those now old ones spiders' webs have covered over, they that are not eternal are ...
New God. Who must of course be false. (Haydock)
Hebrew, "strange "Exodus xx. 2., and Jeremias xxiii. 23. (Calmet)
An express law on this head was a great benefit, (Worthington) as most people had gone astray. (Haydock)